Controller - Jacobsen LF550-H-T4F Safety, Operation And Maintenance Manual

11 PROBLEM SOLVING

11.2 CONTROLLER ____________________________________________________________

The Mower Controller is a solid state device that monitors and controls the electrical functions of the mower. The
controller receives the input signals from switches and sensors in the mower. The controller sends the output signals to
operate relays, solenoids and warning lights. The controller controls and sets the timers and includes logic to control
some mower functions.
For factory help with controller problems, give the hardware revision and software version found on the controller.
The replacement controllers with higher revision levels will be compatible.
Each input and output signal is shown by Light Emitting Diodes (LED) found on the front of the controller. A closed input
switch indicates an active circuit and will illuminate the related LED. An open switch indicates a circuit that is not active
and will turn off the related LED. When the LED is illuminated, the output circuit is active.
Some controller outputs need a group of conditions set before the controller sends the output signal.
For example, to send the output to start the engine, all of these conditions must be true.
• The PTO switch is in the OFF position. (LED OFF)
• The parking brake switch is in the on position. (LED ON)
• The traction pedal is in the Neutral Position. (LED ON)
• The ignition switch is turned to the START position. (LED ON)
When you use the controller to find a solution to a mower problem, always make sure that the ignition power status
LED is illuminated. This LED indicates that the controller is active. The controller needs a minimum of 6 volts to
operate.
Test each circuit and check for the LED to illuminate when you activate or adjust the switch. If an input LED does not
illuminate, a not active condition is indicated. A not active condition could be caused by a blown fuse, a defective switch
or bad electrical connections. Not all of the switches are found on the instrument panel. Refer to the Parts Manual to
find switch locations.
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NOTICE